Not sure where you got your instructions for clearing caches but I found these instructions that are specifically for the J3 that don't match what you found. Try these and see if they get you what you want...
https://www.google.com/url?sa=t&rct=...knJxCcZfKKjlWm
Always be sure to include your device model when searching for information because there are a lot of Samsung Galaxy devices. While there are similarities between devices from the same manufacturer there are also differences as they evolve their hardware and software updates over time.